Articulated suspension systems are known, for example from the Swiss patent 656 787 for slatted mattresses.
This type of device, shown in FIG. 5, comprises resilient means 522, 523 forming a vertical suspension and a pivoting shaft 25, 524 providing an articulation permitting rotation of the slat about a shaft 25 parallel to its longitudinal axis and fixed by a piece 18 to the frame of the bed. At the same time, the device provides connection of the slat with the suspension by means of a sleeve 19. Flanges 28, 29 integral with the pivoting shaft 25 provide resistance to rotation of the suspension piece.
To secure the slat to the suspension piece, it is necessary to have a certain rigidity which is not compatible with the resilience required for the suspension function.
Because of the multiplicity of functions performed by this single piece, the construction is complex resulting in a high production cost. Similarly, the multiplicity of functions requires a compromise between the choice of the resilient qualities of the material. This compromise is prejudicial, either to the resilience function or to the connection function.